“Chicken scratch”, coined by Shakespeare in 1909?

In “Emily Dickinson was a Dinosaur” I conjectured that T. W. Higginson might have been riffing on the idiom chicken-scratch when he described Emily Dickinson’s handwriting as resembling the “famous fossil bird-tracks” of Amherst. Now I’m not so sure.

Higginson published his essay in 1891. But chicken scratch and variants aren’t in OED2 or OED3, nor in Webster 1844. In fact “chicken scratch(es)” or “chicken scratching(s)” don’t seem to be current idioms for handwriting until the early to mid-twentieth century. Before about 1910, chicken scratch refers only to a kind of supplementary chicken feed (and here OED has ‘hen scratch, hen scratching’ s.v. hen).

As far as I can tell, the first use of chicken scratch to refer to bad handwriting is by Shakespeare, in 1909. I mean, by the character of William Shaxper as imagined by Lewis F. Bostelmann in Roger of Rutland: A Drama in Four Acts, in which the playwright adopts a Shakespearean style to dramatize his theory that Roger Manners, Fifth Earl of Rutland (1576-1612) wrote all of Shakespeare’s plays. As Bostelmann explains in the 1911 second edition (which has five acts), “The Stratford swindle must be stopped”! The real truth is that “William Shaxper of Stratford-on-Avon” is a “dummy and strawman for the Earl-author.” And, what’s more, he’s an illiterate fool with poor penmanship:

Rutland. (aside) Poor fellow, now indeed I pity him ! (paper, pen and ink are brought–). Shax. sits at table and muses (near front)– Shax. (aside) Pray God in Heaven, help me out in this;
I cannot write much more than mine own name
And that resembles more a chicken’s scratch
That puts the art of writing to the shame.

Higginson didn’t use scratch, though–that was me connecting his comparison to an idiom of mine. What Higginson said was feet, and there is a similar metaphor to do with chickens recorded in English as early as 1899, eight years after Higginson’s essay:

The hand-writing in our public schools looks now like chicken feet, and should our children be compelled to study the chicken language they would soon become chicken-hearted too. [Gentleman Farmer, vol. 6 (1899)]

The earliest instance of handwriting described as chicken-foot-or-print-like that I can find is in German, but it carries through to the English translation (done two decades before Higginson’s essay):

Hornebog, drawing his sword, pierced the parchment with it, and presented it to his companion, stuck on the point of the blade.”What do these hooks and chickens’ feet mean, Sir Brother?” asked he. [Eng. trans. by Sofie Delffs, Leipzig, 1872]

Perhaps readers can locate earlier examples, or examples in other languages. The French equivalent is pattes de mouche, which isn’t quite close enough.